/**
 * Robotics & Mechatronics Club
 * Resources & Curriculum Stylesheet
 */

/* Filter Bar */
.resources-controls-bar {
  background: var(--bg-surface);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg);
  padding: 1.25rem 1.5rem;
  margin-bottom: 2rem;
  box-shadow: var(--shadow-subtle);
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.controls-top-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.search-box-wrapper {
  position: relative;
  flex: 1;
  min-width: 280px;
}

.search-icon-decor {
  position: absolute;
  left: 1rem;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-muted);
  font-size: 1rem;
  pointer-events: none;
}

.resources-search-input {
  width: 100%;
  padding: 0.75rem 1rem 0.75rem 2.6rem;
  background: var(--bg-secondary);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-md);
  color: var(--text-primary);
  font-size: 0.95rem;
  font-family: var(--font-body);
  transition: all var(--transition-fast);
}

.resources-search-input:focus {
  outline: none;
  border-color: var(--accent-cyan);
  box-shadow: 0 0 15px var(--accent-cyan-glow);
  background: #0f1a30;
}

.resources-meta-stats {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.count-badge {
  font-size: 0.8rem;
  font-weight: 600;
  padding: 0.35rem 0.75rem;
  border-radius: var(--radius-full);
  background: rgba(0, 210, 255, 0.1);
  border: 1px solid rgba(0, 210, 255, 0.25);
  color: var(--accent-cyan);
}

/* Module Pill Buttons */
.module-filter-pills {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  overflow-x: auto;
  padding-bottom: 0.25rem;
}

.module-pill-btn {
  padding: 0.5rem 1rem;
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-full);
  color: var(--text-secondary);
  font-size: 0.82rem;
  font-weight: 500;
  white-space: nowrap;
  transition: all var(--transition-fast);
}

.module-pill-btn:hover {
  background: var(--bg-surface-hover);
  color: #ffffff;
  border-color: var(--border-strong);
}

.module-pill-btn.active {
  background: linear-gradient(135deg, #0284c7 0%, #00d2ff 100%);
  color: #030d20;
  font-weight: 700;
  border-color: transparent;
  box-shadow: 0 0 14px var(--accent-cyan-glow);
}

/* Module Group Blocks */
.module-group-block {
  margin-bottom: 2.75rem;
}

.module-group-header {
  margin-bottom: 1.25rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--border-subtle);
}

.module-pill-tag {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--accent-cyan);
  letter-spacing: 0.08em;
  margin-bottom: 0.35rem;
}

.module-group-title {
  font-size: 1.45rem;
  color: #ffffff;
  letter-spacing: -0.01em;
}

.module-group-desc {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-top: 0.25rem;
}

/* Sessions Cards Grid */
.sessions-cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(360px, 1fr));
  gap: 1.4rem;
}

.session-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  transition: all var(--transition-normal);
  position: relative;
  box-shadow: var(--shadow-subtle);
  overflow: hidden;
}

.session-card:hover {
  transform: translateY(-3px);
  border-color: var(--accent-cyan);
  box-shadow: var(--shadow-elevated);
}

.session-covered-card {
  border-top: 3px solid var(--accent-cyan);
}

.card-top-row {
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
  margin-bottom: 0.95rem;
  width: 100%;
}

.card-top-meta-line {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  width: 100%;
}

.card-badges-line {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.45rem;
  width: 100%;
}

.session-index-pill {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  padding: 0.22rem 0.6rem;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.07);
  color: var(--text-primary);
  white-space: nowrap;
  flex-shrink: 0;
  line-height: 1.25;
}

.session-index-pill.large {
  font-size: 0.85rem;
  padding: 0.3rem 0.8rem;
  background: rgba(0, 210, 255, 0.15);
  color: var(--accent-cyan);
  border: 1px solid var(--accent-cyan);
}

.card-top-row .badge {
  white-space: nowrap;
  flex-shrink: 0;
  border-radius: var(--radius-sm);
  padding: 0.22rem 0.6rem;
  font-size: 0.74rem;
  line-height: 1.25;
}

.session-duration {
  font-size: 0.78rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
  white-space: nowrap;
  flex-shrink: 0;
  margin-left: auto;
}

.session-title {
  font-size: 1.18rem;
  font-weight: 700;
  margin-bottom: 0.65rem;
  color: #ffffff;
}

.session-summary {
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.55;
  margin-bottom: 1rem;
}

/* Material Availability Badges */
.materials-badges-row {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  margin-bottom: 1rem;
  flex-wrap: wrap;
}

.mat-pill {
  font-size: 0.72rem;
  font-weight: 600;
  padding: 0.2rem 0.55rem;
  border-radius: var(--radius-full);
}

.mat-pill-video {
  background: rgba(239, 68, 68, 0.15);
  color: #f87171;
  border: 1px solid rgba(239, 68, 68, 0.3);
}

.mat-pill-doc {
  background: rgba(2, 132, 199, 0.15);
  color: #38bdf8;
  border: 1px solid rgba(2, 132, 199, 0.3);
}

.mat-pill-curated {
  background: rgba(245, 158, 11, 0.15);
  color: #fbbf24;
  border: 1px solid rgba(245, 158, 11, 0.3);
}

.session-key-topics {
  background: var(--bg-secondary);
  border-radius: var(--radius-md);
  padding: 0.85rem 1rem;
  margin-bottom: 1.25rem;
  flex-grow: 1;
}

.topics-title {
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
}

.topics-list {
  list-style: none;
  font-size: 0.82rem;
  color: var(--text-secondary);
}

.topics-list li {
  position: relative;
  padding-left: 1rem;
  margin-bottom: 0.35rem;
  line-height: 1.45;
}

.topics-list li::before {
  content: "•";
  position: absolute;
  left: 0;
  color: var(--accent-cyan);
  font-weight: bold;
}

.topics-list .more-topics {
  color: var(--accent-cyan);
  font-weight: 500;
}

.session-card-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding-top: 0.85rem;
  border-top: 1px solid var(--border-subtle);
}

.session-card-actions .btn-primary {
  flex: 1;
}

/* Session Modal Detail View */
.session-detail-view {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.modal-tags-bar {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 0.75rem;
  flex-wrap: wrap;
}

.module-tag, .format-tag {
  font-size: 0.78rem;
  padding: 0.2rem 0.6rem;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.06);
  color: var(--text-muted);
}

.format-tag {
  color: var(--accent-cyan);
  border: 1px solid rgba(0, 210, 255, 0.25);
}

.session-modal-title {
  font-size: 1.6rem;
  font-weight: 800;
  margin-bottom: 0.5rem;
}

.session-modal-summary {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* Modal Tabs */
.session-modal-tabs {
  display: flex;
  gap: 0.5rem;
  border-bottom: 1px solid var(--border-strong);
  overflow-x: auto;
  padding-bottom: 0.25rem;
}

.s-tab-btn {
  padding: 0.65rem 1.1rem;
  background: transparent;
  color: var(--text-muted);
  font-size: 0.88rem;
  font-weight: 600;
  border-radius: var(--radius-md) var(--radius-md) 0 0;
  white-space: nowrap;
  transition: all var(--transition-fast);
  border-bottom: 2px solid transparent;
}

.s-tab-btn:hover {
  color: var(--text-primary);
  background: rgba(255, 255, 255, 0.03);
}

.s-tab-btn.active {
  color: var(--accent-cyan);
  border-bottom-color: var(--accent-cyan);
  background: rgba(0, 210, 255, 0.08);
}

.session-tab-content {
  display: none;
}

.session-tab-content.active {
  display: block;
  animation: fadeIn 0.25s ease;
}

/* Video Player Enhancements */
.video-player-container {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.video-parts-switcher-bar {
  background: var(--bg-surface);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-md);
  padding: 0.75rem 1rem;
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.parts-label {
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--accent-cyan);
}

.parts-buttons-group {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.part-btn {
  padding: 0.35rem 0.75rem;
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  font-size: 0.8rem;
  font-weight: 600;
  transition: all var(--transition-fast);
}

.part-btn:hover {
  background: var(--bg-surface-hover);
  color: #ffffff;
}

.part-btn.active {
  background: var(--accent-cyan);
  color: #040914;
  border-color: var(--accent-cyan);
}

.video-source-toggle-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}

.source-toggle-title {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.source-pills-row {
  display: flex;
  gap: 0.4rem;
}

.source-pill-btn {
  padding: 0.35rem 0.75rem;
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-full);
  color: var(--text-muted);
  font-size: 0.78rem;
  font-weight: 600;
  transition: all var(--transition-fast);
}

.source-pill-btn:hover {
  color: var(--text-primary);
}

.source-pill-btn.active {
  background: rgba(0, 210, 255, 0.15);
  border-color: var(--accent-cyan);
  color: var(--accent-cyan);
}

.media-player-wrapper {
  background: #020617;
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.8);
}

.native-html5-video {
  width: 100%;
  aspect-ratio: 16 / 9;
  display: block;
  background: #000000;
}

.youtube-player-embed-box {
  width: 100%;
  aspect-ratio: 16 / 9;
  position: relative;
}

.youtube-player-embed-box iframe {
  width: 100%;
  height: 100%;
  border: none;
}

.youtube-placeholder-box {
  width: 100%;
  height: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 2rem;
  text-align: center;
  background: radial-gradient(circle at center, #0d1b33 0%, #030712 100%);
}

.placeholder-icon {
  font-size: 3.5rem;
  margin-bottom: 0.75rem;
  opacity: 0.7;
}

.youtube-placeholder-box h4 {
  font-size: 1.2rem;
  color: #ffffff;
  margin-bottom: 0.4rem;
}

.youtube-placeholder-box p {
  font-size: 0.88rem;
  color: var(--text-muted);
  max-width: 480px;
}

.video-meta-details {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.25rem;
}

.video-meta-header-row {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 1rem;
  margin-bottom: 0.75rem;
  flex-wrap: wrap;
}

.video-meta-details h4 {
  font-size: 1.1rem;
  margin-bottom: 0.35rem;
}

.video-meta-details p {
  font-size: 0.88rem;
  color: var(--text-muted);
}

.video-url-edit-box {
  background: var(--bg-secondary);
  border: 1px solid var(--accent-cyan);
  border-radius: var(--radius-md);
  padding: 1rem 1.25rem;
  margin: 1rem 0;
  animation: fadeIn 0.2s ease;
}

.video-url-edit-box label {
  display: block;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--accent-cyan);
  margin-bottom: 0.45rem;
}

.input-with-button-row {
  display: flex;
  gap: 0.5rem;
}

.input-with-button-row input {
  flex: 1;
}

.edit-help-text {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: 0.35rem;
}

.video-quick-links {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
  margin-top: 1rem;
}

/* Notes Tab */
.notes-markdown-box {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.5rem;
}

.notes-markdown-box h4 {
  font-size: 1.05rem;
  margin-bottom: 0.85rem;
  color: var(--accent-cyan);
}

.learning-objectives-list {
  list-style: none;
  margin-bottom: 1.5rem;
  background: var(--bg-secondary);
  padding: 1rem 1.25rem;
  border-radius: var(--radius-sm);
  border-left: 3px solid var(--accent-cyan);
}

.learning-objectives-list li {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-bottom: 0.5rem;
  line-height: 1.5;
}

.notes-body-text {
  font-size: 0.94rem;
  color: var(--text-secondary);
  line-height: 1.75;
}

.notes-section-heading {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--accent-cyan);
  margin-top: 1.75rem;
  margin-bottom: 0.75rem;
  letter-spacing: -0.01em;
  padding-bottom: 0.4rem;
  border-bottom: 1px solid rgba(0, 210, 255, 0.18);
}

.notes-subheading {
  font-size: 1.02rem;
  font-weight: 600;
  color: #f1f5f9;
  margin-top: 1.35rem;
  margin-bottom: 0.5rem;
}

.notes-main-heading {
  font-size: 1.25rem;
  font-weight: 700;
  color: #ffffff;
  margin-top: 2rem;
  margin-bottom: 0.75rem;
}

.notes-title-heading {
  font-size: 1.35rem;
  font-weight: 800;
  color: #ffffff;
  margin-bottom: 1rem;
}

.notes-paragraph {
  font-size: 0.93rem;
  color: #cbd5e1;
  line-height: 1.75;
  margin-bottom: 0.9rem;
}

.notes-divider {
  border: none;
  border-top: 1px solid rgba(148, 163, 184, 0.2);
  margin: 1.75rem 0;
}

.notes-list {
  list-style: none;
  padding-left: 0;
  margin-top: 0.5rem;
  margin-bottom: 1.15rem;
}

.notes-list li {
  position: relative;
  padding-left: 1.4rem;
  margin-bottom: 0.55rem;
  font-size: 0.92rem;
  color: #cbd5e1;
  line-height: 1.65;
}

.notes-list li::before {
  content: "•";
  position: absolute;
  left: 0.35rem;
  color: var(--accent-cyan);
  font-weight: bold;
}

.notes-num-list {
  padding-left: 1.5rem;
  margin-top: 0.5rem;
  margin-bottom: 1.15rem;
}

.notes-num-list li {
  margin-bottom: 0.55rem;
  font-size: 0.92rem;
  color: #cbd5e1;
  line-height: 1.65;
}

.formula-box {
  background: var(--bg-secondary);
  border: 1px solid var(--border-strong);
  border-left: 3px solid var(--accent-amber);
  border-radius: var(--radius-sm);
  padding: 0.85rem 1.25rem;
  margin: 1.15rem 0;
  font-family: var(--font-mono);
  font-size: 0.88rem;
  color: #f8fafc;
}

.code-inline {
  background: rgba(0, 210, 255, 0.12);
  color: var(--accent-cyan);
  padding: 2px 6px;
  border-radius: 4px;
  font-family: var(--font-mono);
  font-size: 0.86em;
}

/* Downloads List */
.resources-items-grid {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.resource-item-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-md);
  padding: 1rem 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  transition: all var(--transition-fast);
}

.resource-item-card:hover {
  background: var(--bg-surface-hover);
  border-color: var(--accent-cyan);
}

.res-icon-col {
  width: 44px;
  height: 44px;
  background: var(--bg-secondary);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
  flex-shrink: 0;
}

.res-info-col {
  flex: 1;
}

.res-title {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 0.2rem;
}

.res-meta {
  font-size: 0.78rem;
  color: var(--text-muted);
}

.res-meta code {
  background: rgba(255, 255, 255, 0.06);
  padding: 0.1rem 0.35rem;
  border-radius: 4px;
  color: #38bdf8;
}

.resource-item-card.resource-card-revised {
  border-color: rgba(16, 185, 129, 0.5);
  background: linear-gradient(135deg, var(--bg-surface) 0%, rgba(16, 185, 129, 0.05) 100%);
  box-shadow: 0 0 12px rgba(16, 185, 129, 0.12);
}

.revised-status-chip {
  font-size: 0.72rem;
  background: rgba(16, 185, 129, 0.2);
  color: #10b981;
  border: 1px solid rgba(16, 185, 129, 0.4);
  padding: 0.15rem 0.55rem;
  border-radius: var(--radius-full);
  font-weight: 700;
  letter-spacing: 0.02em;
}

.btn-success {
  background: rgba(16, 185, 129, 0.2);
  color: #10b981;
  border: 1px solid rgba(16, 185, 129, 0.5);
}

.btn-success:hover {
  background: rgba(16, 185, 129, 0.35);
  border-color: #10b981;
  color: #ffffff;
}

.res-action-col {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

/* Curated Video Guides Grid */
.curated-library-box {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.5rem;
}

.curated-library-box h4 {
  font-size: 1.1rem;
  color: var(--accent-cyan);
  margin-bottom: 0.35rem;
}

.curated-links-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1rem;
}

.curated-link-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 0.75rem;
  transition: all var(--transition-fast);
}

.curated-link-card:hover {
  border-color: var(--accent-amber);
  transform: translateY(-2px);
}

.curated-cat-tag {
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--accent-amber);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.curated-title {
  font-size: 0.88rem;
  color: var(--text-primary);
  line-height: 1.4;
  flex-grow: 1;
}

.session-modal-footer {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 1rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border-subtle);
}

/* Capstone Project Showcase */
.capstone-hero-card {
  background: linear-gradient(135deg, rgba(14, 26, 48, 0.9) 0%, rgba(19, 36, 68, 0.9) 100%);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  box-shadow: var(--shadow-elevated);
  margin-bottom: 2rem;
  position: relative;
  overflow: hidden;
}

.capstone-hero-card::after {
  content: "🤖";
  position: absolute;
  right: 2rem;
  bottom: 1rem;
  font-size: 8rem;
  opacity: 0.08;
  pointer-events: none;
}

.capstone-badge {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--accent-amber);
  margin-bottom: 0.5rem;
}

.capstone-title {
  font-size: 2.2rem;
  font-weight: 800;
  margin-bottom: 0.35rem;
  color: #ffffff;
}

.capstone-subtitle {
  font-size: 1.05rem;
  color: var(--accent-cyan);
  margin-bottom: 1rem;
}

.capstone-overview {
  font-size: 1rem;
  color: var(--text-secondary);
  max-width: 900px;
  line-height: 1.65;
  margin-bottom: 2rem;
}

.capstone-stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1rem;
}

.cap-stat-card {
  background: rgba(8, 13, 26, 0.6);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.25rem;
}

.cap-stat-number {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--accent-cyan);
  margin-bottom: 0.25rem;
}

.cap-stat-label {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.capstone-grid-details {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
  margin-bottom: 2rem;
}

.capstone-subcard {
  background: var(--bg-surface);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
}

.capstone-subcard h3 {
  font-size: 1.2rem;
  margin-bottom: 1.25rem;
  color: #ffffff;
  border-bottom: 1px solid var(--border-subtle);
  padding-bottom: 0.75rem;
}

.dof-list, .matrix-list {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.dof-item {
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 0.85rem 1rem;
  display: flex;
  align-items: center;
  gap: 1rem;
}

.dof-num {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  padding: 0.25rem 0.5rem;
  border-radius: var(--radius-sm);
  background: rgba(0, 210, 255, 0.15);
  color: var(--accent-cyan);
  white-space: nowrap;
}

.dof-info strong {
  color: #ffffff;
  font-size: 0.92rem;
}

.dof-spec, .dof-motion {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.matrix-item {
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 0.85rem 1rem;
}

.matrix-mod {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--accent-amber);
  margin-bottom: 0.25rem;
}

.matrix-skill {
  font-size: 0.88rem;
  color: var(--text-secondary);
}

/* Capstone BOM Table */
.capstone-bom-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
}

.capstone-bom-card h3 {
  font-size: 1.2rem;
  margin-bottom: 1.25rem;
}

.table-responsive {
  overflow-x: auto;
}

.bom-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}

.bom-table th {
  text-align: left;
  padding: 0.85rem 1rem;
  background: var(--bg-secondary);
  color: var(--text-muted);
  font-weight: 600;
  border-bottom: 1px solid var(--border-strong);
}

.bom-table td {
  padding: 0.85rem 1rem;
  border-bottom: 1px solid var(--border-subtle);
  color: var(--text-secondary);
}

.bom-table tr:hover td {
  background: rgba(255, 255, 255, 0.02);
}

.bom-qty-tag {
  font-family: var(--font-mono);
  font-weight: 700;
  padding: 0.2rem 0.55rem;
  border-radius: 4px;
  background: rgba(245, 158, 11, 0.15);
  color: #fbbf24;
}

/* Logistics View */
.logistics-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
  gap: 1.5rem;
}

.logistics-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg);
  padding: 2rem;
  box-shadow: var(--shadow-subtle);
}

.logistics-icon {
  font-size: 2.2rem;
  margin-bottom: 0.75rem;
}

.logistics-card h3 {
  font-size: 1.3rem;
  margin-bottom: 1.25rem;
  color: #ffffff;
}

.logistics-items {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
  margin-bottom: 1.5rem;
}

.log-row {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  padding-bottom: 0.65rem;
  border-bottom: 1px solid var(--border-subtle);
}

.log-label {
  font-size: 0.78rem;
  text-transform: uppercase;
  color: var(--text-muted);
  font-weight: 600;
}

.log-val {
  font-size: 0.95rem;
  color: var(--text-primary);
  font-weight: 500;
}

.req-group {
  margin-bottom: 1rem;
}

.req-title {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--accent-cyan);
  margin-bottom: 0.4rem;
}

.bullet-list {
  list-style: none;
}

.bullet-list li {
  font-size: 0.88rem;
  color: var(--text-secondary);
  padding-left: 1rem;
  position: relative;
  margin-bottom: 0.35rem;
}

.bullet-list li::before {
  content: "✔";
  position: absolute;
  left: 0;
  color: var(--accent-emerald);
  font-size: 0.75rem;
}

.instructor-bio h4 {
  font-size: 1.2rem;
  color: #ffffff;
}

.instructor-role {
  color: var(--accent-amber);
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 0.75rem;
}

.instructor-summary {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 1.5rem;
  line-height: 1.6;
}

/* Enhanced Zoom Logistics Widget */
.zoom-highlight-card {
  border-color: rgba(0, 210, 255, 0.4);
  background: linear-gradient(135deg, var(--bg-surface) 0%, rgba(0, 210, 255, 0.04) 100%);
  box-shadow: 0 0 20px rgba(0, 210, 255, 0.08);
}

.zoom-credentials-widget {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  background: var(--bg-secondary);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-md);
  padding: 0.85rem 1rem;
  margin-bottom: 1.25rem;
  box-sizing: border-box;
  max-width: 100%;
}

.zoom-cred-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.85rem;
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 0.7rem 0.95rem;
  box-sizing: border-box;
  min-width: 0;
}

.zoom-cred-meta {
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
  min-width: 0;
}

.cred-label {
  font-size: 0.72rem;
  text-transform: uppercase;
  color: var(--text-muted);
  font-weight: 700;
  letter-spacing: 0.05em;
}

.cred-value {
  font-size: 0.95rem;
  color: #38bdf8;
  font-weight: 700;
  white-space: nowrap;
}

.copy-btn {
  padding: 0.35rem 0.75rem;
  font-size: 0.78rem;
  border-radius: var(--radius-sm);
  white-space: nowrap;
  flex-shrink: 0;
}

.zoom-actions-grid {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.zoom-primary-btn {
  padding: 0.75rem 1rem;
  font-size: 0.95rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
}

/* Interactive Tools View */
.tools-showcase-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.75rem;
}

.tool-interactive-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg);
  padding: 2rem;
  box-shadow: var(--shadow-subtle);
}

.tool-header {
  margin-bottom: 1.5rem;
}

.tool-header h3 {
  font-size: 1.3rem;
  color: #ffffff;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.tool-header p {
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-top: 0.25rem;
}

/* Resistor Visual Box */
.resistor-graphic-box {
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.75rem;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.5rem;
}

.resistor-body-svg {
  width: 240px;
  height: 52px;
  background: #e2d9c8;
  border-radius: 26px;
  border: 3px solid #b5a995;
  display: flex;
  align-items: center;
  justify-content: space-evenly;
  position: relative;
  box-shadow: inset 0 2px 6px rgba(0,0,0,0.3);
}

.resistor-body-svg::before, .resistor-body-svg::after {
  content: "";
  position: absolute;
  top: 50%;
  width: 40px;
  height: 6px;
  background: #cbd5e1;
  transform: translateY(-50%);
}

.resistor-body-svg::before {
  left: -40px;
}

.resistor-body-svg::after {
  right: -40px;
}

.color-band {
  width: 14px;
  height: 100%;
  border-radius: 2px;
}

.resistor-inputs-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.form-group label {
  display: block;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-muted);
  margin-bottom: 0.35rem;
}

.form-select, .form-input, .form-textarea {
  width: 100%;
  padding: 0.65rem 0.85rem;
  background: var(--bg-secondary);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-md);
  color: var(--text-primary);
  font-family: var(--font-body);
  font-size: 0.9rem;
}

.form-select:focus, .form-input:focus, .form-textarea:focus {
  outline: none;
  border-color: var(--accent-cyan);
}

.calc-result-box {
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.25rem;
}

.result-main-val {
  font-family: var(--font-heading);
  font-size: 1.8rem;
  font-weight: 800;
  color: var(--accent-cyan);
  margin-bottom: 0.25rem;
}

.result-sub-detail {
  font-size: 0.85rem;
  color: var(--text-muted);
}

@media (max-width: 900px) {
  .sessions-cards-grid {
    grid-template-columns: 1fr;
  }
  .capstone-grid-details, .tools-showcase-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  .resources-controls-bar {
    padding: 1rem 0.85rem;
    gap: 0.85rem;
    margin-bottom: 1.25rem;
  }

  .controls-top-row {
    flex-direction: column;
    align-items: stretch;
    gap: 0.75rem;
  }

  .search-box-wrapper {
    width: 100%;
    min-width: 0;
  }

  .resources-meta-stats {
    width: 100%;
    justify-content: space-between;
  }

  .module-filter-pills {
    padding-bottom: 0.35rem;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
  }

  .module-filter-pills::-webkit-scrollbar {
    display: none;
  }

  .module-pill-btn {
    padding: 0.4rem 0.75rem;
    font-size: 0.76rem;
  }

  .sessions-cards-grid {
    grid-template-columns: 1fr;
    gap: 1rem;
  }

  .session-card {
    padding: 1.15rem 0.85rem;
  }

  .card-title {
    font-size: 1.08rem;
  }

  .session-actions-grid {
    grid-template-columns: 1fr !important;
    gap: 0.5rem;
  }

  .session-action-btn {
    width: 100%;
    justify-content: center;
  }

  .capstone-grid-details,
  .tools-showcase-grid,
  .kinematics-inputs-grid,
  .battery-inputs-grid {
    grid-template-columns: 1fr !important;
  }

  .calculator-card {
    padding: 1.15rem 0.85rem;
  }

  .session-modal-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.75rem;
  }

  .session-modal-title {
    font-size: 1.25rem;
  }

  .video-switcher-tabs {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
    width: 100%;
  }

  .video-switcher-tabs::-webkit-scrollbar {
    display: none;
  }
}

/* ==============================================
   YOUTUBE API UPLOAD STUDIO & INSTRUCTOR STYLES
   ============================================== */
.instructor-video-actions-row {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  flex-wrap: wrap;
}

.btn-yt-upload {
  background: linear-gradient(135deg, #dc2626 0%, #b91c1c 100%);
  color: #ffffff;
  border: 1px solid rgba(239, 68, 68, 0.5);
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  box-shadow: 0 0 10px rgba(220, 38, 38, 0.25);
  transition: all var(--transition-fast);
}

.btn-yt-upload:hover {
  background: linear-gradient(135deg, #ef4444 0%, #dc2626 100%);
  box-shadow: 0 0 18px rgba(239, 68, 68, 0.5);
  transform: translateY(-1px);
}

.yt-auth-status-box {
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.15rem 1.25rem;
  margin-bottom: 1.25rem;
  transition: all var(--transition-fast);
}

.yt-auth-status-box.is-connected {
  border-color: rgba(52, 211, 153, 0.4);
  background: rgba(16, 185, 129, 0.06);
}

.yt-connected-account-badge {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}

.yt-connected-profile {
  display: flex;
  align-items: center;
  gap: 0.85rem;
}

.yt-channel-avatar {
  width: 42px;
  height: 42px;
  border-radius: var(--radius-full);
  border: 2px solid var(--accent-cyan);
  object-fit: cover;
}

.yt-channel-avatar-placeholder {
  font-size: 1.75rem;
}

.yt-profile-text strong {
  display: block;
  font-size: 0.95rem;
  color: #ffffff;
}

.yt-profile-text span {
  display: block;
  font-size: 0.78rem;
  color: var(--accent-emerald);
}

.yt-setup-guide {
  margin-top: 0.9rem;
  border-top: 1px dashed rgba(255, 255, 255, 0.1);
  padding-top: 0.75rem;
}

.yt-setup-guide summary {
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--accent-cyan);
  cursor: pointer;
  outline: none;
  user-select: none;
}

.yt-setup-guide-content {
  margin-top: 0.75rem;
  font-size: 0.8rem;
  color: var(--text-muted);
  line-height: 1.6;
  background: rgba(0, 0, 0, 0.3);
  padding: 0.85rem 1rem;
  border-radius: var(--radius-sm);
  border-left: 3px solid var(--accent-cyan);
}

.yt-setup-guide-content ol {
  padding-left: 1.25rem;
  margin-top: 0.35rem;
}

.yt-setup-guide-content li {
  margin-bottom: 0.35rem;
}

.yt-setup-guide-content code {
  color: var(--accent-cyan);
  background: rgba(0, 210, 255, 0.1);
  padding: 0.1rem 0.35rem;
  border-radius: 3px;
  font-family: var(--font-mono);
}

.yt-upload-dropzone {
  border: 2px dashed rgba(0, 210, 255, 0.3);
  border-radius: var(--radius-md);
  padding: 1.75rem 1.5rem;
  text-align: center;
  background: rgba(15, 23, 42, 0.6);
  cursor: pointer;
  transition: all var(--transition-fast);
  margin-bottom: 1.25rem;
}

.yt-upload-dropzone:hover, .yt-upload-dropzone.drag-active {
  border-color: var(--accent-cyan);
  background: rgba(0, 210, 255, 0.08);
  box-shadow: 0 0 20px rgba(0, 210, 255, 0.15);
}

.yt-dropzone-prompt {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.4rem;
}

.yt-dropzone-icon {
  font-size: 2.2rem;
  color: var(--accent-cyan);
}

.yt-dropzone-title {
  font-size: 0.95rem;
  font-weight: 600;
  color: #ffffff;
}

.yt-dropzone-hint {
  font-size: 0.78rem;
  color: var(--text-muted);
}

.yt-file-selected-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: rgba(0, 210, 255, 0.1);
  border: 1px solid var(--accent-cyan);
  border-radius: var(--radius-md);
  padding: 0.75rem 1rem;
  width: 100%;
}

.yt-file-selected-left {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.yt-file-icon {
  font-size: 1.6rem;
}

.yt-file-info strong {
  display: block;
  font-size: 0.88rem;
  color: #ffffff;
  word-break: break-all;
}

.yt-file-info span {
  font-size: 0.75rem;
  color: var(--accent-cyan);
}

/* Progress Box */
.yt-upload-progress-box {
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.75rem;
  text-align: center;
  margin-top: 1rem;
}

.yt-progress-track {
  width: 100%;
  height: 12px;
  background: rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-full);
  overflow: hidden;
  position: relative;
  margin: 1.25rem 0 0.85rem 0;
}

.yt-progress-fill {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, #00d2ff 0%, #38bdf8 50%, #34d399 100%);
  border-radius: var(--radius-full);
  transition: width 0.2s ease;
  box-shadow: 0 0 12px rgba(0, 210, 255, 0.6);
}

.yt-progress-stats-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.82rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
  margin-bottom: 1.25rem;
}

/* Success Box */
.yt-upload-success-box {
  background: rgba(16, 185, 129, 0.06);
  border: 1px solid rgba(52, 211, 153, 0.4);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  text-align: center;
  margin-top: 1rem;
}

.yt-success-icon {
  font-size: 2.5rem;
  margin-bottom: 0.5rem;
}

.yt-success-embed-wrapper {
  margin: 1.25rem 0;
  border-radius: var(--radius-md);
  overflow: hidden;
  aspect-ratio: 16 / 9;
  background: #000;
  box-shadow: var(--shadow-elevated);
}

.yt-success-embed-wrapper iframe {
  width: 100%;
  height: 100%;
  border: none;
}